SAN FRANCISCO, Oct. 8 (Xinhua) -- The University of California, Berkeley, has received a grant to study whether food is a significant source of the antibiotic-resistant bacteria that cause urinary tract infections (UTI), the most common bacterial infections in the developed world.
The 560,000 U.S. dollars grant was awarded earlier this week by the U.S. federal government agency Centers for Disease Control and Prevention (CDC) based in Atlanta, Georgia, to the research project led by Lee Riley, a professor of infectious diseases at the UC Berkeley School of Public Health.
Treatment of urinary tract infections, which disproportionately affect women, has become more difficult in recent years because E. coli, the most common bacteria that cause urinary tract infections, have become increasingly resistant to commonly used antimicrobial agents. Researchers do not know how big a role food plays in spreading the antibiotic-resistant forms of the bacteria, which is the key question Riley' s team aims to answer.
"Understanding what proportion of multidrug-resistant urinary tract infections are attributable to food sources will change the way we calculate the burden of foodborne disease and the impact of antimicrobial use in food animal husbandry," Riley was quoted as saying in a UC Berkeley news release.
An estimated 11 percent of women in the United States report at least one physician-diagnosed urinary tract infection per year. Some urinary tract infections are acquired by the introduction of particular strains of E. coli into the bladder during sex, but these infections can also occur when E. coli are ingested, colonize in the intestine and then spread to the bladder.
In 1999, when Riley's lab began investigating how urinary tract infections were acquired, they found that in three geographically diverse communities, a single E. coli strain, called clonal group A, accounted for nearly half of the drug-resistant urinary tract infections in women. The strain was also found in 30 percent of males in the study. The widespread prevalence of a single strain, which is known to have resistance to common antibiotics, suggested the E. coli was spread by an outbreak and not by sex.
"That was when we first suspected transmission from food," Riley said, adding that "if antibiotics contaminate food, then their potential to cause drug-resistant urinary tract infections is a huge public health issue."
With the new funding, Riley's lab at UC Berkeley will coordinate with the CDC to compare the infection-causing E. coli found on campus with the meat E. coli database of the U.S. Food and Drug Administration (FDA), and work with the CDC to analyze the data.
The team will seek to get a clear picture of the influence of food or diet on the spread of multidrug-resistant E. coli that increase a woman's risk for urinary tract infections by collecting urine samples from patients at UC Berkeley's Tang Center with urinary tract infections to estimate the prevalence of drug-resistant E. coli strains.
The researchers will also study the genes of these strains and look for clues about how diet and behavior impact the acquisition of these bacteria and then compare E. coli from the patients to E. coli found in locally consumed retail meat to see if there is any overlap.
The UC Berkeley study is one of 34 projects the CDC is funding with 14 million dollars through its Broad Agency Announcement to support activities related to the CDC Antibiotic Resistance Solutions Initiative and implement the tracking, prevention and antibiotic stewardship activities outlined in the National Action Plan for Combating Antibiotic-Resistant Bacteria. These projects aim to find new approaches to combat antibiotic resistance, including research on how the microorganisms that are naturally found in the human body, called the microbiome, can be used to predict and prevent infections caused by drug-resistant organisms.